[bug]: Comment external_id is deduplicated per project instead of per work item #10195

Is there an existing issue for this?

• I have searched the existing issues

Current behavior

Creating a work item comment with external_source and external_id returns 409 when any work item in the same project already has a comment with that pair. The check belongs to one work item's comment endpoint, but it filters by project only:

apps/api/plane/api/views/issue.py:1565 (create) and :1735 (update), branch preview:

IssueComment.objects.filter(
    project_id=project_id,
    workspace__slug=slug,
    external_source=...,
    external_id=...,
).exists()

So one external event that touches several work items in a project, written with one key per event, can record a comment on the first work item only. The rest get 409, and the id in the response points to a comment on a different work item.

Steps to reproduce

1. Take two work items A and B in one project.
2. Create a comment on A:

curl -X POST "$HOST/api/v1/workspaces/$SLUG/projects/$PROJECT/work-items/$A/comments/" \
  -H "X-API-Key: $KEY" -H 'Content-Type: application/json' \
  -d '{"comment_html":"<p>probe</p>","external_source":"probe","external_id":"scope-1"}'

Result: 201.

3. Send the same request for B.

Result: 409 with {"error":"Work item comment with the same external id and external source already exists","id":"<id of the comment on A>"}.

Expected: 201 on B. The 409 should apply only to a repeat on the same work item, by adding issue_id to the filter. If project-wide uniqueness is intended, it would help to say so in the API docs.

Environment

Production

Browser

Other

Edition

Commercial

Version

v3.3.0